Implement 'format' filter (original) (raw)

Implement 'format' filter according to the jinja2 specification:

Apply python string formatting on an object:

{{ "%s - %s"|format("Hello?", "Foo!") }}
    -> Hello? - Foo!

Actually, {fmt} library has got all necessary facilities for analyze python format strings so, it could be good idea to reuse this facilities during resolving this issue.